Measuring apparatus



June 12,1934. A, NOBLE 1',962,324

MEASURING APPARATUS Filed July 15. 1932 2 Sheets-Sheet 1 WW I -1 K r i i LA INVENTOR ALPHONJO N05 BY I r I ATTOR NEY June 12; 1934. A. NOB LE 1,962,324

"MEASURING APPARATUS Filed July 15. 1952 2 Sheets-Sheet 2 YIINVENTOR ALPHo/vs'o Nos/.5

ATTORNEY Patented June 12, 1934 I UNITED. STATES PATENT OFFICE MEASURING APPARATUS Alphonso Noble, Naugatuck, Conn.,"assignor to The Bristol Company, Waterbury, Conn., a corporation of Connecticut Application July 15, 1932, Serial No. 622,630 201m. (01. 73-410) The invention relates to measuring apparatus, may be of any well known or special design. In and more especially to apparatus for'measuring the present embodiment, the element 13 reprethe eifects, particularly the difference between sents a. compensating element such as a barothe effects, of two variable conditions, for exmetric responsive element intended as a memp W Varyi g fluid pressures. ber adapted to compensate for the effect of baro-' 60 It has for an object the provision of a measurmetric variations on the other element 14. The ing instrument which will afford direct indi latter also is a fluid pressure-actuated element cations of the difference between, or the algebraic which is designed to measure some extemalpressum of, the effects of twoindependentlyoperatsure or temperature change and is, for this end,

ing conditions or measuring systems, each of provided with a tubular outlet to which exwhichis permittedto actfreely upon mechanism ternal connection may be made in any well for efiecting movement of an indicating or reknown manner. cording element, or controlling member. The The present invention is concerned more espe invention has for a further object the provision cially with the means for communicating the 15 of a novel linkage arrangement between, or for movement of the two pressure-actuated elements 70 combining the effects of, the said two measuring 13 and. 14 to the measuring orcontrolling memy ber 12 common thereto. The latter is shown in In carrying out the invention, two'independthe form of a lever pivotedat and having an I ently operating responsive or measuring sysarm 21\ extending beyond said pivot. To this 20 terns are arranged to transmit forces or movearm is fulcrumed a further lever 22 and prefer- (I ments respectively to opposite ends of a lever, the ably at the latters middle point 23. Thus, the fulcrum of which is arranged to float in that it is lever 22 is carried by the measuring member and carried by an element which is movable about a any movement of said lever will be communifixed pivot. The said lever thus swings as' a cated thereto.

25 whole about this pivotal point, and the points Movement of the lever 22 is derived from the 80 of application of the two forces or motions from two aforesaid pressure-actuated elements through the respective measuring systems are so chosen intermediate mechanism including links 24 and that equivalent resulting movements efiect no '25 pivotally connected respectively to the oppochange in the position of the element, as when site ends of the lever and preferably at equal disthe two said systems are submitted simultanetances from its fulcrum. The opposite ,ends of 85 ously to equal changes; or,by suitably arrangthe links are connected respectively to the arms ing the intermediate connections or responsive 26 and 2'7 of bell cranks whose opposite arms systems, the effects on the lever may be additive. are linked to vertically movable rods 28 and 29 The nature of the invention, however, will best movable by the respective pressure-actuated elebe understood when described in connection with ments.v 90 the accompanying drawings, in which: Any movement of either of: these elements will Fig. his a front elevation of an instrument thus be communicated through the mechanism casing, with cover removed,.and of the novel aforesaid to the lever 22, and when unequal will mechanism contained therein. cause said lever to move as a whole about the 40 Fig. 2 isafragmentary vertical section through pivot point 20, carrying with it the measuring 95 the casing and an elevation of the contained member 12 which thus responds to the algebraic mechanism. sum of the movements of the two pressure-actuq Fig. 3 is a kinematic diagram illustrating the ated elements, or to any diiference in their moveaction of the measuring apparatus. ment, this depending upon the mechanical ar- Referring to the drawings, 10 designates a Lrangement for transmitting movement from the 100 suitable instrument casing in which is mounted said pressure-actuated elements. v a chart support 11 and over which is adapted to The mounting of the links 24 and 25 is such, move in well-known manner a controlling memmoreover, that normally the longitudinal axis of her or measuring element as the pen arm 12 the former link actuated from the element 13' adapted to be actuated in the manner hereinpasses, for example, through the fixed pivot 30 5 after set forth from two independent measuring for the arm 2'7 of the oppositepressure-actuated systems. element as well as through the pivot point 20 These systems may embody, for'example, the about which the pen arm 12 and its extension two fluid pressure-actuated elements 13 and 14 21 swing. mounted on the back of the casing, and which Similarly, the longitudinal axis of the link 25 no passes through a fixed pivot 31 for the arm 26 of the pressure-actuated element 13; and the point of attachment of the first-named link to the lever/22 is substantially at, the pivot point 20 for the measuring arm. Several pivot points, as indicated,.are provided for the respective arms in initially adjusting the same; and the effective action 'of these arms is really represented by a line normal to the links 24 and 25 to which they are attached, as indicated in Fig. 3 of the drawings. By this expedient, errors due to the angular movements are minimized, as with the structure set forth the links upon deflection depart from parallelism a minimum amount since the throw of a link is substantially parallel'as being tangent to the arc described by the individual arms, or rather the efiective normals represent- 7 ing these arms.

By the foregoing arrangement, reference being had more particularly to Fig. 3 of the drawings, I

it will be noted that an angular movement (a) of the arm 26 will cause an. angular movement (a') of the member 12; and similarly an angular movement (b) of the arm 27 will cause an angular movement (b') thereof. If these movements are equal, the anguar movements (a) and (b), upon opposite sides of the lever 22 will have a net effect upon the measuring member12 which carries the same to the initial or zero position; and, correspondingly, unequal movement of the aforesaid arms will result in a differential effect upon the said member 12. I

Furthermore, by changing the location of the point of attachment of a link 24 or 25 to the lever 22, or by changing the effective length of an arm 26 M27, the effects of equal angular movable about a fixed pivot, a member movable about a fixed pivot, a lever carried by the movable member which affords a floating fulcrum therefor, a pair of links connecting the respective arms with opposite ends of the said lever, the longitudinal axis of one of the links normally passing through the pivot point of the arm actuated by the opposite responsive system, and the longitudinal axis of the other link normally passing through the pivot point of the other arm.

2. An instrument, comprising two independent responsive systems, an arm actuated by one of the systems and movable about a fixed pivot, an arm. actuated by the other of the systems and movable about a, fixed pivot, a member movable about a fixed pivot, alever carried by the movable member which aifords a floating fulcrum therefor, a pair of links connecting the respective arms with opposite ends of the said lever, the longitudinal axis of one of the links normally passing through the pivot point of the arm actuated by the opposite responsive system, and the longitudinal axis of the other link normally passing through the pivot point of the other arm and the point of attachment of one of the links to the lever being normally at the pivot point of the movable member.

v ALPHONSO NOBLE. 

